Wow I just found the reason why my Stax systems couldn’t sound like good old 80’s Stax sound in my home. It was main power breakers loosen and bad contacted tap screws! My house is over 30 years old house. I just loosen a bit/re-tightend up them very hard. Wow just Wow! It sounds Utterly Creamy and Ultra Real! Good old Stax sound came back in my home! As you know, any contact points of any electric circuits are MOST unreliable parts among all/any electronic parts/cuircuits. and any old/bad contact points have wrong resistance. If current run resistance it makes voltage = noises. E(main power noise voltage) = I(all home electronics total high current) * R (old/bad contact point resistance) Its simple Ohm’s law and law of Physics. you may remember that Robb Watts of Chord said -180dB or -300dB mains noise are audible...In his opinion not mine Lol. warning. I absolutely don’t recommend DIY re-tighned up tap screws of main brakers. it can be very dangerous! Let professionals do it. hope this some newbies helps. happy listening! Rob mentioned about power cord diffrences in this video.